Clinical Study On The Influence Of Orthodontic Traction Timing Of Maxillary Impacted Anterior Teeth On Root And Periodontal Tissues

Objective:The changes of the root and periodontal tissues of the roots of the two types of roots after traction treatment were compared by the treatment of the maxillary impacted anterior teeth with the development of the roots and the undeveloped roots.To explore the optimal traction timing of the maxillary impacted anterior teeth.Methods:From September 2016 to February 2019,27 patients from the Department of Stomatology of the Affiliated Hospital of Youjiang Medical College of Medicine,including the treatment of maxillary ambushed anterior teeth surgery combined with orthodontic traction,a total of 28 maxillary impacted anterior teeth.According to the inclusion criteria,they were divided into two groups,namely the complete root development group and the undeveloped root group.Each group has 14 teeth,and the contralateral tooth of the same name was used as a control.All patients were treated by the same group of medical staff in the aseptic operation,closed closed window priming,and the same group of medical staff were treated with orthodontic traction.The CBCT and clinical examination measurements were used to record the relevant measurements of the root and periodontal tissues before orthodontic traction and orthodontic traction.Using t test,rank sum test,?~2 test statistical method to compare the measured indicators before and after the anterior orthodontic traction,the contrast between the impacted teeth and the contralateral teeth,and the comparison between the two groups of occlusal teeth,to evaluate the orthodontic traction timing for the two groups of ambushed roots and periodontal tissues influences.Results:(1)Root length:the length of the root were not fully developed of the occlusal tooth after the orthodontic traction is longer than that of the anterior root before the orthodontic traction(P<0.05),but shorter than the length of the root after the same tooth of the contralateral side(P<0.05)).The root length of the roots were fully developed after complete traction was shorter than that of the roots before the traction?the roots were not fully developed,and the length of the contralateral teeth after traction(P<0.05).(2)Thickness of root canal wall:The thickness of root canal wall after orthodontic traction of the root were not fully developed of the tooth was larger than that of the root wall before orthodontic traction(P<0.05),and the teeth which root was not fully developed,their wall thickness was the same as that of the contralateral side of the same tooth and root development after the orthodontic traction(P>0.05).The thickness of the root canal wall after the orthodontic traction of the fully developed dental root is the same as the thickness of the root canal wall before the orthodontic traction,and the thickness of the root canal after the orthodontic orthodontic traction.(P>0.05).(3)The orthodontic traction time of the implanted teeth with not fully developed roots was shorter than that of the roots with complete root development(P<0.05).(4)Adhesive width and thickness of the labial bone plate:The thickness of the attachment ridge and the thickness of the labial bone plate after orthodontic traction of the two groups of occlusal teeth are smaller than the width of the iliac crest after orthodontic traction of the opposite side of the same tooth,and the labial plate of the labial bone Thickness(P<0.05).The width of the attachment ridge and the thickness of the labial bone plate were the same after the orthodontic traction of the two groups(P>0.05).(5)pulp vitality:after orthodontic traction,between the two groups of occluded teeth?between the two groups of ambushed teeth and the contralateral tooth of the same name,the pulp activity was the same and normal(P>0.05).(6)Root bending:The number of bending after orthodontic traction of the two groups of occlusal teeth was the same(P>0.05).The number of curved roots before and after orthodontic traction was the same in the undeveloped roots(P>0.05).Conclusion:(1)Although the root length of the implanted orthodontic traction after the root is not fully developed is shorter than that of the contralateral tooth,the root can continue to develop to the Nolla stage 9-10,The traction time of a complete ambush tooth is significantly longer than that of not fully developed occlusal tooth.After the root of the fully developed occlusal tooth is in place,the root length is absorbed more than the occlusal tooth that is not fully developed.During the traction process,the thickness of the root canal wall under normal development was normal,and the pulp activity was normal.(2)Closed fenestration combined with orthodontic traction will result in a certain degree of loss of the thickness of the labial bone and the width of the attachment raft.(3)In orthodontic traction treatment,the ambushed anterior teeth with undeveloped roots have the advantages of rapid periodontal tissue reconstruction,short orthodontic traction time and light root absorption.Its overall efficacy is better than that of an implant with complete roots.